Machine tool



R. H. CLARK MACHINE TOOL Oct. 31, 1950 10 Sheets-Sheet l Filed June e, 1946 INVENTQR. RmaERT H. ELHRK wimw R. H. CLARK MACHINE TOOL Oct. 31, 1950 10 Sheets$heec 2 Filed June 6, 1946" I INVENTOR. R013 ER'T H. CLERK W.,B :KW

fiTTuRNE s Filed June 6, 1946 o m N Oct. 31, 1950 CLARK 2,528,299

MACHINE TOOL l0 Sheets-Sheet 4 0 OFF 23% r INVENTOR. RDEIERT H.ELHRK R. H. CLARK MACHINE TOOL Oct. 31, 1950 10 Sheets-Sheet 5 Filed June 6, 1946 Z K k x m R \vN T H x m L mr n m MS mH W T I s New R a E m w N R D R T T w H R. H. CLARK MACHINE TOOL Oct. 31, 1950 10 Sheets- Sheet 6 Filed June 6, 1946 ENE mu! en! Oct. 31, 1950 R. H. CLARK 1 2,528,299

momma: TOOL Filed June 6, 1946 10 Sheets-Sheet 7 INVENTOR. RuEsR-r H-ELFIRK BY F| 3 U W z/ w fiw m FITTDRNEYE Oct. 31, 1950 R. H. CLARK MACHINE TOOL 10 Sheets-Sheet 10 Filed June 6, 1946 INVENTOR. R'EIEERTH. ELFIR'K HTTDR'NE 5 \snl Patented Oct. 31, 1950 MACHINE TOOL Robert H. Clark, Solon, Ohio, assignor to The Warner & Swasey Company, Cleveland, Ohio,

a corporation of Ohio Application June 6, 1946, Serial No. 674,894

This invention relates to a machine tool and particularly to a machine tool adapted to perform rapid machining and threading operations upon relatively small work pieces, although the invention may be advantageously employed in machining tools for different types of work pieces.

Another object of the invention is to provide a machine tool which is so constructed and its operations so controlled that it will function in an improved, rapid and efficient manner and thus enable the work pieces to be more economically produced.

Another object of the invention is to provide a machine tool which is particularly suited for machining relatively small work pieces at high speeds and wherein a number of machining operations are to be performed upon each work piece successively, with each machining operation of relatively short duration, thereby requiring frequent changes in speed and direction of operation.

Another object of the invention is to provide in a machine tool of the type having an electric motor for driving the spindle at different speeds in opposite directions, improved means for controlling the speed and direction of motor operation.

A further object is to provide in a machinetool of the type having a variable speed spindle and a slide provided with an indexible turret, improved means for controlling the speeds, the direction of movement and the starting and stopping of the spindle and which means is actuated in part by the indexing of the turret and in part by the movements of the slide.

Another and important object is to provide in a machine tool of the type havin a reversible multispeed electric motor for driving the spindle and a slide provided with an indexible turret, improved means for controlling the speeds, the direction of rotation and the starting and stopping of the motor for each step of a work cycle and which means can be preset and then actuated in part by the indexing of the turret and in .part by the movement of the slide.

A still further object of the invention is to provide in a machine tool having in combination with the features above referred to improved means for braking the motor to stop the rotation of the spindle and for locating the spindle in a predetermined position for purposes of loading and unloading.

Another object is to provide in a machine tool in combination with the features hereinbefore enumerated, improved and novel means for causing the multispeed motor to drive the said spindle at different speed ranges, i. e., a high speed range and a low speed range, and which means is controlled by the indexing of the turret.

v Further and additional objects and advantages 15 Claims.

a embodiment of the invention which is to follow.

Referring to the accompanying drawings 11- lustrating said embodiment of the invention,

Fig. 1 is a front elevational. view of a machine tool to which the invention has been applied, the machine tool being shown for purposes of illustration as a turret lathe wherein the slide is manually moved and the turret is indexed by the movement of the slide.

Fig. 2 is a fragmentary rear elevational view of the machine tool shown in Fig. 1 but on a larger scale.

Fig. 3 is a fragmentary top plan view of the machine tool shown in Fig. 2.

Fig. 4 is a detached sectional view taken substantially on line 4--4 of Fig. 3 looking in the direction of the arrows.

Fig. 4a is a fragmentary elevational view taken substantially from line la-4a of Fig. 4.

Fig. 5 is a fragmentary view similar to Fig. 3 but on a larger scale and shows the construction of the machine tool partly in top plan and partly in section.

Fig. 6 is a rear view of the portion of the machine tool shown in Fig. 5 and is partly in elevation and partly in section, the section being taken substantially on line 6-45 of Fig. 5 looking in the direction of the arrows.

Fig. '7 is an end view on a larger scale taken from the left hand end of Figs. 5 and 6 and with the end cover plate removed.

Fig. 8 is a sectional view taken substantially on line 8--8 of Fig. 7 looking in the direction of the arrows.

Fig. 9 is a fragmentary front elevational view taken substantially from line 9-9 of Fig. '7, looking in the direction of the arrows.

Fig. 10 is a detached detail sectional view on a larger scale taken on line l0lfl of Fig. 5, looking in the direction of the arrows.

Fig. 11 is a detached view of a portion of the mechanism shown in Fig. 5 and is on a larger scale and with the parts shown in different relationship.

Fig. 12 is a view similar to Fig. 11 but shows the parts in a still different relationship.

Fig. 13 is a view similar to Figs. 11 and 12 but shows the parts in a still different relationship.

Fig. 14 is a developed view of the most left hand and of the lowermost cam disk carrying drums shown in Fig. 7, which drums are identical in construction.

Fig. 14a is a plan view of one of the cam disks of the drum shown in Fig. 14.

Fig. 15 is a developed view of the uppermost cam disk carrying drum shown in Fig. 7.

Figs. 15a and 151) are plan views of one of the cam disks of the drum shown in Fig. 15 and disclose two different operative positions of said disk.

Fig. 16 is a developed view of the most right hand cam disk carrying drum shown in Fig. "I.

Fig. 16a is a plan view of one of the cam disks I of the drums shown in Fig. 16.

Fig. 17, Sheet 6, is a detached elevational view on a larger scale of the control panel shown in Fig. 1 with certain positions of the control lever indicated by dash lines.

Fig. 18 is a sectional view taken on line |8|8 of Fig. 1'1 looking in the direction of the arrows.

Fig. 19 is a detail sectional view taken substantially on line |9-|9 of Fig. 18.

Figs. 20, 21, 22, 23, 24, 25 and 26 are sectional views taken, respectively, substantially on lines 20-20, 2l2|, 22-22, 23-23, 2424, 25-25 and 2626 looking in the direction of the arrows.

Fig. 27 is a chart showing the relationship of the various SS switches on the control panel.

Fig. 28 is a chart showing the relationship of the various MS switches on the control panel.

Fig. 29 is a detached elevational view of the spindle and drive therefor and includes a braking mechanism for the motor, a positioning mechariism for the spindle and mechanism for imparting high and low speed ranges to the spindle.

Fig. 30 is an end elevational view of the brake mechanism and is taken looking at the right hand end of a portion of Fig. 29.

Fig. 31 is a wiring diagram of the power circuits for the motor and the speed and direction controls therefor. I

Fig. 32 is a wiring diagram of the electrical control circuits for the machine.

Figs. 33 and 34, taken together, are a wiring diagram of the electrical circuits for the machine corresponding with the power and control circuits disclosed in Figs. 31 and 32 but laid out in accordance with Patent Office standards and requirements.

Referring to Fig. 1, the machine tool shown therein is a turret lathe and comprises a bed 35 supported on spaced pedestals 36 and 31. A headstock 38 is carried by one end of the bed 35 and rotatably supports the work spindle 39 and chuck 39a and which spindle is driven by a reversible multispeed electric motor 40 supported by the pedestal 36 and operatively connected with the spindle 39 by means of belts 4| extending around a pulley on the motor shaft 42 and a pulley on a shaft 43, see Fig. 29. The shaft 43 carries gears 44 and 45 which are freely rotatable relative to the shaft and mesh, respectively, with a large gear 46 and a smaller gear. 41 fixed to the spindle 39. The shaft 43 is provided with shiftable clutch means whereby the gear 44 or the gear 45 can be clutched to said shaft and for purposes of illustration said clutch means is shown herein as a positive clutch element 48 adapted to be shifted in either direction from a neutral position axially of the shaft 43 to a position where it is positively engaged with the gear 44 or to a position where it is positively engaged with the gear 45. The mechanism for shifting the clutch element 49 will be explained in detail hereinafter and it should be suflicient for the present to note that the multispeed motor 40 can drive the spindle 39' at a plurality of different speeds either in low speed range or in high speed range, depending upon which of the gears 44 or 45 is clutched to the shaft 43. The bed 35 is provided with longitudinally extending ways 49 which are parallel to the work spindle 39 and adjustably support a saddle 50 and on which is a turret slide having an indexible turret 52, see Fig. 1. The saddle 56, in a manner well known in the art, can be moved to and clamped in adjusted position on the ways 49, whilethe slide 5| is manually moved on the ways of the saddle by means of a tumstile 53 fixed to a shaft 54 which carries a pinion 55, see Fig. 5, and is rotatably supported in the saddle with said pinion meshing with a rack carried by the slide as is well known in the art.

The turret 52 is indexed automatically by 'the movement of the slide and is locked and clamped by well known mechanism for that purpose and therefore not illustrated herein. The central stud of the indexible turret 52 extends into the slide 5| and has fixed thereto a bevel gear 56, see Fig. 6, which meshes with a bevel gear 51 fixed to one end of a shaft 58 that is parallel to the ways 49. The shaft 58 extends rearwardly within the slide 5| and passes through and is fixed to a stop roll collar 59. The collar 59 abuts against one side of a bearing boss formed in the slide 5| and said collar is rigidly connected to the end of a reduced portion of a stop roll 60 and which reduced portion rotatably interfits said bearing boss while the shoulder on the stop roll at the inner end of the reduced portion engages the opposite side of the bearing boss upon the collar 59, wherefore the stop roll is held against relative endwise movement. with respect to the slide 5| but can rotate relative thereto.

The stop roll 66 rearwardly of the reduced portion thereof is in the form of a sleeve and the rear end of the stop roll is rotatably supported in a bearing boss 6| formed in a supporting bracket attached to the end of the slide and having a sleeve portion 62 surrounding the sleeve portion of the stop roll and an integral cam disk supporting drum housing portion 63 for a purpose later to be explained. The stop roll collar 59 is provided with a plurality of circularly spaced openings concentric to the shaft 58 and aligned with threaded bores formed in the reduced portion of the stop roll. Adjustable stop screws 64 extend through the threaded bores of the stop roll and through the openings in the collar 59 and can be adjusted longitudinally relatively to the stop roll by means of wrench heads formed on the stop screws within the sleeve portion of the stop roll. The stop screws will correspond in number to the difierent indexed positions of the turret and it will be noted that as the turret is indexed the stop roll will be simultaneously indexed through the bevel gears 56, 51 and the shaft 55 to bring the stop screws successively in line with a movable stop member 65.

The stop member 65 is fixed to a cam rod 66 which is slidably supported in a portion of the base and which portion is provided with a postive stop lug 61 against which the movable stop member 65 abuts after it has been moved by the stop screw which is in alignment therewith. The positive stop lug 61 is provided with a recess which slidably receives a pin 65 carried by the movable stop member 65, wherefore said member and the rod 66 are held against rocking movement about the axis of said rod.

It will be seen that when the slide 5| moves forwardly toward the chuck 39a carried by the work spindle 39 the movable stop member 65 will be engaged by one of the stop screws 64 when the slide approaches its limit of forward movement and during the remainder of the forward movement of the slide for non-threading operations the movable stop member 65 will be moved into engagement with the positive stop lug 61 and the forward movement of the slide thus positively arrested. This movement of the movable stop member 65 compresses the coil spring 69 which surrounds the rod 66 between a collar HI fixed to the rod and a part of the saddle 50. The rod 66 has its right hand end as viewed in the drawings slidably supported in a bore formed in the saddle 50 for a purpose later to be pointed out. The cam rod 66 is provided with a stepped recessed cam portion for the purpose of controlling the automatic reversal of the motor 40 particularly during threading operations, with the lowermost part of said cam portionconnected to the first step by an inclined camming surface H, while said first step is connected to the second step by a similar inclined camming surface 12, see Figs. 5, 11, 12 and 13.

The saddle 50 is also provided with a bore which communicates perpendicuarly with the bore in which the cam rod 86 slides and which bore slidably supports a cam plunger '3 which has a reduced portion extending through a shouldered bushing 14 and outwardly of the saddle 5|], said bushing serving as an abutment for one end of a coil spring 15 which surrounds the reduced portion of the plunger and has its end abutting the enlarged portion thereof as clearly shown in the drawings.

The reduced portion of the cam plunger 13 extends outwardly of the bushing 14 in the saddle 50 at the rear of the machine and into a housin 76 secured to the rear side of the saddle. An arm 11 is pivotally supported intermediate its ends at 18 in the housing and said arm carries a switch LS3 which is actuated by a switch button 1 l9 axially aligned with the reduced portion of the cam plunger 13. The switch LS3 is located on one side of the pivot 18 for the arm 11 and said arm on the opposite side of said pivot is provided in its edge with a stepped holding notch formed of two portions 80 and 8|. A spring pressed plunger 82 supported internally of the housing 16 contacts the inner edge of the arm I! and normally acts to rock said arm about the pivot 18 in an anticlockwise direction as viewed in the drawings and to hold the arm against a part later to be referred to.

The housing 16 is provided with an internal bearing boss which rockably supports the vertically extending shaft 83 that has on its lower end a finger portion 84 and on its upper end a thumb lever 85, the hub of which is provided with a pointer portion 86 that cooperates with indicia indicatin the two hifferent operative positions of the finger portion 84, namely, the letters L and E representing, respectively, "Late and Early, see Figs. 3 and 10.

The adjustments provided for by the thumb lever 85 refer to early and late threading operations. As will later be explained, other control mechanism functions in conjunction with the switch-LS3 for threading operations. The finger portion 84 of the shaft 83 extends into the recess forming the stepped holding portions 80 and 8| of the arm 11. It will be seen that when the thumb lever 85 is in the position shown in Figs. 5 and 11 the finger portion 84 is in the holding recess 80 and the lever arm 11 is substantially parallel to the cam rod 66. This is the E or early position and will be used when the threading operation involves the use of a solid tap or solid die.

It will be noticed by reference to Fig. 5 that when the lever arm 11 is in the position just referred to and the plunger 13 extends into the deepest portion of the cam recess of the rod 66 the reduced end of the plunger is contacting the switch actuating button 19 but is not depressing said button. It will further be noted that during a threading operation when a stop screw 64 has contacted and moved the abutment member 65 and shifted the rod 66 from the position shown in Fig. 5 to the position shown in Fig. 11 the plunger 13 has been moved by the inclinedsurface H to compress the spring 15 and to depress the switch actuating button 19 to actuate the switch LS3 carried by the arm 11 to reverse the motor 40 in a manner later to be explained.

It will be noted that after the parts are in the position shown in Fig. 11 the movable abutment member 65 is still out of contact with the positive stop lug 61. The spindle will coast in its forward rotation causing a continued forward movement of the slide due to the threading engagement between the tool and the work piece. When the switch LS3 is actuated to effect a reversal of the motor 4|] the threaded tool tends to back off and disengage itself from the work piece when the motor rotates in the reverse direction, whilethe operator simultaneously effects the rearward movement of the slide during the backing off of the tool by manually turning the turnstile 53. It will be understood that the amount of movement of the slide due to the coasting of the spindle depends upon the coarseness or fineness of the thread being cut on the work piece since the slide will'move farther in the case of a coarse thread for the same number of coasting revolutions then it would in the case of a fine thread. If the operator finds during the set-up of the machine that the thread cut on the work piece is too short or too long he may adjust the stop screw 64 to cause the latter to engage the movable stop member 65 earlier or later as the case may be.

In the use of collapsible taps or collapsible dies for threading a work piece the motor 40 can be reversed at a later point than was the previously described case, since the collapsing of the tap or die terminates the thread cutting and therefore the coasting of the motor does not cause any forward movement of the slide. In the instance just referred to the operator turns the thumb lever 85 to bring the pointer 86 into line with the letter L indicating late operation of the switch LS3 and such movement of the thumb lever brings the parts into the relationship shown in Fig. 12. 1

It will be seen that the positioning of the thumb lever 85 in the manner stated has caused the finger 84 to move out of the holding recess and into the holding recess 8| of the lever arm 11, with the result that said arm has been rocked in a clockwise direction from the position shown in Fig. 11 to the position shown in Fig. 12 and which movement of the arm compresses the spring plunger 82 and moves the switch actuating button 19 out of contact with the reduced extended end of the plunger 13, although the inner end of said plunger is in the lowermost portion of the cam recess in the rod 66. Consequently when the slide is moving forwardly and the stop screw 64 contacts the movable abutment member 65 and shifts the rod 66 to compress the spring 69 the plunger 13 will travel up the inclined surface H and onto the first step and this movement of the plunger 13 brings the extended end of the plunger into contact with the switch actuating button 19 but does not depress said button. The forward movement of the slide continues and the rod 66 is further shifted, with the resu1tthat the 7 end of the plunger I3 rides up the inclined surface I2 and onto the second step of the rod 66, wherefore the extended end of the plunger depresses the switch actuating button I9 and actuates the switch LS3 as indicated in Fig. 13. This actuation of the switch LS3 effects a reversal of the motor 40. At the time that the switch LS3 is actuated to reverse the motor 40 the collapsible tap or die has completed its threading operation and will collapse in the usual manner, wherefore the threaded relationship between the threaded tool and the work is terminated and consequently any coasting of the motor and the spindle before reversing will not result in any further forward movement of the slide.

The switch box or housing I6 has fixed to its outer and left hand side as viewed in Fig. 2 a switch box 81 which houses a normally open switch LS5, the switch button 88 of which is depressed momentarily to close said switch in the rearward movement of the slide by a dog 89 fixed to the side of the slide as indicated in Fig. 3. The switch box 8! also houses a switch LSI I, the purpose of which will later be explained, see Fig. 4. The electrical conduits from the switches LS3, LS and LSI I extend from the switch boxes and 81 through a flexible cable 90 to the cam disk supporting drum housing portion 63 where said conduits are properly connected to four switches later to be referred to and contained within said housing portion 63.

It-will be understood that the switches LS3, LS5, LSI I and the switches in the housing 63 are also suitably connected to the control panel of the motor 40 by electrical conduits located within the tube 9I extending from the switch box I6 to the pedestal 36 located beneath the headstock. The end of the flexible cable 90 which is attached to the housing portion 63 moves with the slide 5| as indicated by full and dash lines in Fig. 2 and said cable is guided and supported in a V-shaped support 92 secured. to a fixed part of the machine which in this instance is the pan.

The switch box 81 rockably and slidably mounts an actuating plunger 93, see Fig. 4, which is provided with an annular groove that is normally so positioned as to receive the extended switch button 94 of the normally closed switch LSI I. The plunger 93 has fixed thereto within the switch box 81 a collar 95 that limits the movement of the plunger toward the right as viewed in Fig. 4. A stop arm 96 is fixed to the other end of the plunger 93 and a coil spring 91 surrounds said plunger between the switch box 81 and the stop arm 96 and acts to normally hold the plunger in a position wherein the collar 95 contacts the interior of the switch box and the annular groove of the plunger is in position to receive the extended switch button 94. The stop arm 96 and the plunger 93 are normally rocked to a position wherein said stop arm is substantially horizontal, as indicated by dash line position of Fig. 4a., and in which position the stop arm is out of the path of movement of the plate on which is located the dog 89. The stop arm 96 is in its horizontal position when the machine is utilizing a plurality of different tools mountedon the various faces of the turret 52 for performing a plu- However, there are occasions when the machine will be employed with only a single tool on one face of the turret to perform a single machining operation on the work piece and after each such machining operation the turret need not be indexed while the spindle should be stopped for the purpose-of unloading and loading the work pieces. In such a situation the normally closed switch LSII is employed to effect stopping of the spindle before the slide has moved rearwardly to turret indexing position and to maintain the spindle stopped until the slide is again moved forwardly. When it is desired to I accomplish this the operator swings the stop arm 96 from the dash line position of Fig. 4a into the vertical full line position of Figs. 4 and 4a and plate which carries the dog 89. the slide is moved rearwardly upon the complewherein said stop armwill lie in the path of the Consequently as tion of a machining operation upon the work piece the plate will engage the stop arm 96 substantially simultaneously with the depression ofthe switch button 88 of the switch LS5 by the dog 89. The continued rearward movement of the slide causes the plate to move the stop arm 96 and the plunger 93 rearwardly against the action of the spring 91 unti1 the switch button 94 of switch LSII has moved out of the annular groove in the plunger and has been depressed by the plunger to open the switch LSII and, as will later be explained, to stop' the motor 40 and the rotation of the spindle.

The stop arm 96 provides a positive stop so that the operator knows he has moved the slide rearwardly the required distance to open switch LSI I, it being understood that this occurs prior to the slide reaching turret indexing position, wherefore the turret 52 is not indexed and the single tool carrying face remains in operative position. As soon as the spindle has stopped the operator unloads the finished work piece from the chuck in the spindle and loads a new work piece therein, after which he again moves the slide forwardly by the turnstile whereupon the sprin 91 restores the plunger 93 and stop arm 96 to their most right hand position as indicated in Fig. 4 and the switch LSII automatically closes as soon as the switch button align with the groove in the plunger. The forward movement of the slide also causes the dog 89 to momentarily depress the switch button 88 of the normally open switch LS5 to momentarily close said switch and complete the circuit to start the motor as will be explained in relation to the diagram of Fig. 32.

The sleeve portion of the stop roll 60 within the cam disk supporting drum housin 63 and to the left of the bearing boss 6|, as viewed in Fig. 5, has fixed thereto a gear 98 which meshes with four gears 99, I00, IOI and I02. The gears 99 and I00 are formed on similar cam disk supporting drums I03 rotatably supported in the housing 63 on shafts I04 mounted in bosses formed interiorly of the housing 63, see Figs. 5 and 6. The gears IOI and I02 are similarly formed, respectively, on cam drums I05 and I06 correspondingly rotatably supported within the housing 63 on similar shafts I04. It will be seen that each time the stop roll 60 is rotated by the indexing movement of the turret the two identical cam drums I03 and the cam drums I05 and I06 will have a corresponding rotative indexin movement.

The two cam drums I03 each is providedin this instance with six equally spaced circularly which carries the gear 98 cooperates with the switch LSIO while the cam drum I03 which carries the gear I cooperates with the switch LS4. In each indexed position of the cam drums I03 a recess of said drums will be aligned, respectively, with the switch buttons of switches LS4 and LSIO. The drums I03 each carry six identical switch button actuating disks I08 formed on shouldered or enlarged portions of plungers I09 andwhich portions slidably interfit the recesses I01. The plungers I09 slidably pass through openings in the drums and have fixed to their outer ends buttons IIO. Each button H0 is provided on its side adjacent to the cam drums with a radially extending V-shaped ridge III adapted to cooperate with a complementary V-shaped groove II2 formed in the adjacent face of the drum.

It will be seen that when the plungers I09 are rotated to one position relative to the drum the ridges III can extend into the grooves H2 and the plungers will be fully extended while when the plungers are rotated from such position through an arc of 180 the ridges III will extend transversely to the grooves I I2 and be in engagement with shallow notches on the face of the drums and the plungers will be held in retracted position.

In each recess I01 there is provided a coil spring II3 which acts against the enlarged portion of the respective plunger and tends to move said plunger toward the left as viewed in Fig. 8. Consequently, it will be apparent that when the ridges III are aligned with the grooves II2 the springs 3 act to move the plungers to their most left hand or extended position at which time the disks I08 are located so as to engage and actuate the switch buttons of the switches LS4 and LSIO as the case may be when the drums are indexed.

It will also be noted that when the plungers are retracted and the ridges I II extend transversely to the grooves II2 the springs II3 are compressed and the disks I00 are located in a plane wherein they will not actuate the switch buttons as the drums are indexed.

As previously stated, there are six of the plungers I09 in each cam drum I03 corresponding, in this instance, to the six operative steps of a work cycle and said plungers can be selectively positioned in correlation to the different operative steps either to actuate the switch buttons or to be inactive with respect thereto as the drums are indexed.

. In Fig. 14 the plungers I09 of both drums I03 which function, respectively, in steps I, 4 and 5 of the operative cycle are shown in extended positionsuch that the disks I08 thereof will engage and depress the switch buttons of switches LS4 and LSIO as the cam drums are indexed in relation to the indexing of the turret. Also it will be noted that the plungers I09 corresponding to operative steps 2, 3 and 6 are in retracted position; wherefore the indexing of the cam drums for such operative steps will not cause the disks I08 of these plungers to actuate the switch buttons ofthe switches LS4 and LSIO, as the case may be. The buttons IIO of each drum I03 may be provided with indicia representing the different operative steps of the work cycle, wherefore the operator by opening the cover 03a of the housing 83 can adjust the plungers I 00 to effect or not to efiect actuation of the switches I54 and LSIO in the different steps of the cycle as desired. It will be understood that the same switch and switch button are illustrated in Fig. 14 by the full line and dash line showings. In addition, it will be understood that the plungers of the drum which is associated with switch LS4 may have one arrangement while the plungers of the drum associated with switch LSIO may have the same or a different arrangement. The switch LS4 is a two-position switchgand controls the high and low speed of the motor as will be explained in connection with the wiring diagram of Figs, 32, 33 and 34. The switch LSIO is atwoposition switch and controls the energl'z'ation and deenergization of solenoids H4 and II 5 as will also be explained in connection with the wiring diagram, The solenoids H4 and H5 effect the actuation of a pivoted lever II6 which is operatively connected to the adjustable clutch element 48, see Fig. 29, wherefore said switch LSIO Ill) - cumferences.

controls the high and low speed ranges of the spindle by selectively engaging the clutch element 48 with either the gear 44 or the gear 45.

The drum I05 which carries the gear ml is likewise provided, in this instance, with six recesses II! that are spaced about a circle concentric to the shaft I04 and said recesses face toward the switch buttons of normally open switch LS2 and two position switch LSI, and one of said recesses will be aligned with both of said switch buttons in each indexed position of the drum I05. The drum I05 carries six plungers I I8, the enlarged or shouldered portions of which slidably interfit the recesses III while said plungers slidably extend through openings in the drums and are provided on their ends beyond said openings with operating buttons II 9. The opposite ends of the plungers adjacent the enlarged portions thereof are provided with cam disks I20 and have a central diametrically extending raised portion I20a from each side of which the disks taper downwardly to their cir- Each cam disk I20 will as the drum is indexed successively come into alignment with the switch buttons of both switches LS2 and LSI and will act in certain operative positions now to be described to actuate one or both of said switch buttons as the drum is indexed or in another position of the plungers will be inactive with respect to both of said switch buttons.

Each button H9 is provided on its face adlacent to the drum I05 with a radially extending V-shaped ridge or lug I2I and said ridge can be positioned by turning the button and plunger to contact the face of the drum to hold the plunger and cam disk I20 fully retracted as shown in position I of Fig. 15 or it can be positioned to engage in a relatively shallow V-sha-ped groove I22 formed in the face of the drum to allow the plunger and cam disk I20 to be partially extended as shown in position 2 of Fig. 15 or it can be positioned in a deeper radially extending V-shaped groove I23 to allow the cam disk and plunger to be fully extended as shown in position 3 of Fig. 15 A coil spring I24 is mounted in each recess II I to act on each plunger and tends to hold the latter in extended position.

Intermediate the switch buttons of the switches LS2 and LS! and the cam disk which is currently aligned with said switch buttons is a supporting arm I25 carried by the housing 03 and slidably mounting a pin I26 which has one 11 end adapted to contact the cam disks I20 while its other end is provided with a disk I21 adapted to engage the switch buttons of the switches LS2 and LS1.

It will be noted that in position I of Fig. 15 the switch buttons of both switches are fully extended and that the switch button of switch LS2 projects outwardly of the switch a greater distance than does the switch button of switch LS'I. It will be seen that as the cam drum is indexed to positions I, 2,3 and 6 no effect will be had on either of the switch buttons since the plungers IIB corresponding to these positions are fully retracted and therefore the pins I26 will lightly engage the raised portions I20a of the cam disks but the pins will not be moved. When the drum I is indexed to position 4, the plunger II8 correlated to said position being partly extended, the pin I26 will ride upon the raised portion I20a of the cam disk and said pin and disk I21 will be moved to depress the switch button of switch LS2 and to close said switch which, as will be later explained, is a normally open switch controlling the automatic reversal of the motor. In position 4 the switch LS! is not actuated. Then as the drum I05 indexes to position 5, the plunger IIB corresponding to said position being fully extended, the raised portion I20a of the cam disk of said plunger will move the pin I26 and-the disk I21 still farther to depress the switch button for switch LS1 which latter switch is a two-position switch as will later be explained, in connection with the diagrams oi Figs. 32, 33 and 34. It will be understood that when the button of switch LS1 is depressed the button of switch LS2 is farther depressed in the switch closing direction.

All of the cam disks I20 are shown positioned in Fig. with the raised portions Ia thereof extending in a. chordal direction. Referring to Fig. 15, two of the cam disks I20 are shown with the left hand disk positioned with the raised portion I20a. extending in a chordal direction as shown in Fig. 15a and with the plunger in its partially extended position wherein switch LS2 is actuated but not switch LS1.

In Fig. 15 the right hand cam disk I20 is shown turned 90 from the previously mentioned cam disk and with the raised portion I20a thereof extended as indicated in Fig. 15b and at right angles to its position as shown in Fig. 15a. Still re. ferring to Fig. 15 it will be seen that as the drum I05 indexes the pin rides off the left hand cam disk I20, whereupon the switch LS2 momentarily opens and then the pin rides up the inclined portion of the right hand cam disk I20 and onto the raised portion I20a thereof to again close switch LS2.

This arrangement effects momentary opening of switch LS2 for interrupting a holding circuit later to be described in connection with the wiring diagrams of Figs. 32, 33 and 34. If two adjacent plungers IIB of the drum I05 are partially extended or completely extended and the raised portions I20a of their cam disks extend in a chordal direction, as indicated in Fig. 15a, then in indexing from the preceding operative step to the next operative step the pin I26 remains in engagement with the raised portions I20a of the two cam disks merely passing from one to the other during the indexing movement and the switches LS2 and LS1 are not affected by such indexing movement.

The indexible cam drum I06 which has formed thereon the. gear I02 is provided in this instance with six recesses I28 facing toward the switch LS6 carried by the housing 63 and with the switch button of which the cams of the drum I06 cooperate. Piungers I29 extend into the recesses I28 and are guided therein by annular portions I30, said plungers also slidably extending through openings in the drum and having fixed on their outer ends buttons I3 I.

The plungers beyond the annular portions I30 are each formed with a pair of spaced lugs I32 whichmount a fulcrum pin I33. A cam I34 is pivotally mounted on each fulcrum pin I33 by means of spaced legs depending from said cam while a rat trap spring I35 mounted on said pin acts to maintain the cam I34 in its normal or raised position in a plane parallel to the adjacent face of the drum. The cams I34 are of general rectangular shape, as indicated in Fig. 16a, and are provided at one end with an elongated gradually upwardly inclined portion I36 while their opposite ends are provided with short beveled surfaces I31. one longitudinal edge of the cams is formed with a short beveled surface I38 while the other longitudinal edge I39 thereof is straight. Each button I3I is provided on its side adjacent to the drum I06 with a V-shaped ridge or lug I40 adapted to bear against the adjacent face of the drum to retain the plungers and cams fully retracted or to engage in any one of three V-shaped grooves I4I, I42 or I43 formed in the face of the drum and spaced apart when the plungers are fully extended to a position wherein the cams will engage and actuate the switch button of the switch LS6.

A coil spring I44 is mounted in each recess in surrounding relation to the plunger therein and acts against the annular portion I30 to normally urge the plunger and its cam to fully extended position unless the latter is held retracted by the engagement of the lug I40 with the face of the drum. The switch LS6 is a normally closed switch located in the start and. stop circuit as will later be described in connection with the diagrams of Figs. 32, 33 and 34.

Referring to Fig. 16 it will be seen that the plungers I29 of the drum I06 correlated to operative steps I, 2, 3, 4 and 5 are in fully retracted position and hence the cams I34 of these plungers do not actuate switch LS6 during the first five operative steps of the work cycle and as the drum indexes. The plunger I29 corresponding to the sixth operative step is in extended or projected position and is turned so that the cam I34 thereof is positioned with its long dimension in the direction of indexing movement. Hence when the drum indexes from position 5 to position 6 the button of switch LS6 will ride up the inclined surface I36 of this cam I34 and onto the raised flat surface of the cam and will remain on such surface after the drum has been completely indexed to the sixth operative step, wherefore switch LS6 will be held open throughout the sixth operative step and this will result in the motor 40 being deenergized and the spindle stopped during the sixth step as will be explained in connection with the wiring diagrams of Figs. 32, 33 and 34. This condition is desired for purposes of unloading and loading the work pieces as will later be referred to in the description of the operative cycle.

It will be understood that when the plungers I29 are fully extended and are turned so that the cams thereof are in the position of the cam I34 of plunger No. 2 then the indexing of the drum I 08 from one step to the next step causes the button of switch LS6 to ride up the inclined surface I38 of the cam and onto the raised portion thereof to depress the switch button and momentarily open switch LS6 and when the indexing movement is completed said switch button will have ridden off of the narrow dimension of the cam and switch LS8 will again be closed. This is for'the purpose of momentarily braking the holding circuit around switch LS as will be fully explained in connection with the wiring diagram of Fig. 32.

Referring to the cam I34 of the first operative step as shown in Fig. 16, it will be noted that said cam is turned 180 with respect to cam for step No. 2. Assuming that the plunger for step No. I is fully extended, it will be understood that when the drum I06 indexes from the sixth step to the first step the switch button of switch LS6 simply rocks the cam I34 about its pivot I33 and against the action of the spring I35 until the indexing movement is completed, at which time the cam rides to its normal position and the switch button is located intermediate the cams of steps I and 2. The tripping of the cam I34 by the switch button does not actuate switch LS6.

The cam I34 for the first operative step may be positioned as just described so as to enable the operator should he desire to do so to back index the turret from position I to former position 6 to stop the spindle as will be explained. When the operator back indexes the turret, as just referred to, the switch button of switch LS6 rides up the incline I38 of the No. I cam and onto the high part of the cam, with the result that switch LS6 is opened momentarily as the button travels across the narrow width of the cam and is then closed. The momentary opening of the switch LS6 interrupts the holding circuit for switch LS5 and the motor is deenergized and the spindle is stopped. When the operator wishes to proceed with step No. I he again indexes the turret from position 6 to position I in the forward direction as has been previously explained and the switch button merely trips the cam I34 and the switch LS6 remains closed. As soon as the operator moves the slide forwardly and the switch LS5 is momentarily closed by said slide the motor is again actuated, the spindle revolves and a holding circuit is established around switch LS5 as will later be pointed out.

It will be understood that the arrangements of the plungers in the drums I03, I05 and I06 as shown in Figs. l4, l5 and 16 are selected purely for purposes of illustration and that such arrangements may be varied to meet different operative requirements of the machine.

As shown in Figs. 1 and 1'7 a control panel I45 is secured to the front side of the headstock 38 and said control panel carries a master switch control lever I46 which is fixed in a lever bracket I41, see Fig. 18. The lever bracket I41 in its lower portion and adjacent to the panel I45 is provided with a recess I48 into which extends the projecting end of a switch shaft I49 later to be referred to. A bearing pin I50 is carried by the bracket I41 and extends through the shaft I49 and forms a pivot about which the bracket and the lever I46 can be rocked from the full line position of Fig. 18 to the dash line position thereof, it being noted that the lower right hand portion of the bracket I41 is beveled to permit this rocking movement and to form a stop to limit the extent thereof. Bracket I41 is provided with a vertically extending recess in which is slidably mounted a spring pressed plunger I5I which engages the upper side of the shaft I48 and which functions in conjunction with a pin I52 carried by the bracket and engaging the underside of the shaft to return automatically the bracket I41 and the lever I46 when released from their outwardly swung position i. e., the dash line position of Fig. 18, back to their normal or full line position. The recess in the bracket I41 engageswith flat portions of the shaft I49, wherefore said bracket I41, the lever I48 and the shaft I49 can be rocked about the axis of the shaft into any one of four different positions.

The bracket I 41 above the recess I48 is provided with a flat segmental shaped surface adjacent the panel I and said surface contacts a switch rod I53 which is slidably supported by the panel I45 and has at its inner or right hand end, as viewed in Fig. 18, a recess portion housing a coil spring I54 which abuts against a reversing switch LSI and functions to urge the switch rod I53 toward the left but said rod is normally .held against the action of the spring by the bracket MT. The switch button I55 of the reversing switch LSI contacts the bottom of the recessed right hand end of the switch rod I53 and said rod normally maintains said button depressed for forward actuation of the motor 40. However, when the operator rocks the lever I46 and the bracket I41 from the full line position of Fig. 18 into the dash line position thereof the rod I53 moves toward the left under the action of the spring I54 and the switch button I55 follows the movement of the rod and the switch LSI is actuated for reverse operation of the motor 40. As soon as the operator releases the lever I46 the spring pressed plunger I5I overcomes the action of the spring I54 and restores said lever, the bracket I41 and the rod I 53 to the position shown in full lines in Fig. 18, at which time the button I55 of the switch LSI is again depressed and said switch is set for forward operation of the motor.

The switch shaft I49, as previously stated, is rockably supported in the panel I 45 and it will be noted by reference to Fig. 18 that the rear end of said shaft is rockably supported in a plate I56 carried by a plurality of parallel rods I51 secured in and projecting rearwardly from the panel I45. The switch shaft I49 is provided with a plurality of axially spaced shoulders I58, I59, I60, I6I, I62, I63, I64, I65 and I66. A pin I61 extends between the shoulders I58 and I59 and is parallel to the shaft I49 but is spaced radial y with respect thereto, see Fig. 19. Two actuating pins I68 and I69 extend between the shoulders I59 and I 60 and said pins are parallel to the shaft I49 but radially spaced therefrom, with the pin I68 angularly spaced from the pin I69, see Fig. 20. A single actuating pin I 10 extends between the shoulders I60 and I6I in radially spaced but parallel relationship to the shaft I49. Two actuating pins HI and I12 extend between the shoulders I6I and I62 in parallel radially spaced relationship to the shaft I49 with the pin I1I angularly spaced from the pin I12. A single actuating pin I13 extends between the shoulders I62 and I63 in spaced parallel relationship to the shaft I49. Between the shoulders I63 and I64 extends a single actuating pin I 14, also arranged in radiallv spaced parallel relationship with respect to the shaft I49. Likewise a single actuating pin I15 extends between the shoulders I64 and I65 while between the shoulders I65 and I66 three angularly spaced actuating pins I16, I11 and I18 extend in parallel radially spaced relationship 15 relative to the shaft I49. The pins I61, I and I18 are located in the same relative angular position with respect to each other. Actuating pin I is depressed 30 from actuating pins I61, I10 and I18. Actuating pins I69, I12, I13 and I11 are angularly displaced 30 from actuating pin I15 or 60 from actuating pins I61, I10 and I18. Actuating pins I68, I1I, I14 and I16 are displaced 90 from actuating pins I61, I10 and I18. Four of the rods I51 are grouped in pairs above and to the left of the shaft I49, as viewed in Fig. 19 and these rods support cooperating switch contacts I19 and I80 located so as to extend past the shaft I49 and between the shoulders I58, I59, I60, I60, I6I, I6I, I62, I62, I63, I63, I64, I64, I65 and I65, I66 and the switches formed by the pairs of contacts I19 and I80 are hereinafter designated as switches MSI, M82, M83, M84, M85, M86, M81 and M88, see Fig. 18. Each of the contacts I19 and I80 has a clip portion I8I which embraces the rods I51 and holds the contacts in proper position on the rods.

It will be understood that the contacts I19 and I80 are suitably insulated from the rods and at their upper ends are provided with binding screws I82, whereby electrical conduits can be connected to the contacts. Each contact I80 is provided intermediate its end with an offset portion I83 arranged to be engaged by its respective actuating pin or pins to close the contacts I19 and I80, it being understood that when said portion is not engaged by its respective actuating pin or pins the resilience of the contacts maintain the same normally separated.

When the lever I46 is in the High position i. e., the full line position of Fig. 1'1, the contacts I 19 and I80 of switches MSI, M83, M85 and M81 are open while the actuating pins I68, I1I, I14 and I16, respectively, of switches M82, M84, M86 and M88 have engaged the portion I83 of their cooperating contact arm I80 and have closed the contacts I19 and I80 of said switches. When the lever I46 is moved to the ll-ow" position of Fig. 1'7 the contacts of switches MSI, M83, M86 and M81 remain open. At this time the pin I69 of switch M83 has come into engagement with the portion I83 01 its contact arm I80 and thus the contacts I19 and I80 of switch M82 are held closed in the low position of the lever. Also at this time the actuating pin I12 of switch M84 functions to hold the contacts of said switch closed as does also the actuating pin I11 of switch M88. In addition, in the low position of the lever the actuating pin I13 of switch M85 has come into engagement with the portion I83 of its contact arm to effect the closure of the contact arms I19 and I80 of said switch. When the lever I46 is in Release Braking" position of Fig. 17 the contacts of switches M8I and M83 remain open. Also at this time the actuating pins of switches MS2,'MS4 and M88 are out of engagement with the portion I83 of the respective contact arms I80 and hence the contacts of said switches are open. In addition the contacts of switches M85 and M86 are opened since the actuating pins I 13 and I14 of said switches are out of engagement with their respective contact arms I80 at the time the actuating pin I15 of switch M81 has functioned to close the contacts of said switch, in other words, in the Release Brake position of the lever I46 all of the MS switches are opened except switch M81. In the Off position of the lever I46, as shown in Fig. 17, the actuating pins I61 of switch MSI, I10 of switch M83 and I18 of switch M88 have engaged their respective contact arms to close the latter while the actuating pins of switches M82, M84, M88. M88 and M81 are out of engagement with their respective contact arms and said switches are open.

The panel I45 below the rods I51 and the MS switches just described supports a plurality of rearwardly extending parallel rods I84 with said rods supporting at their rear ends a plate I85. The rods I84 of the upper group of rods are arranged in cooperating pairs similar to the arrangement of the rods I51 to support a plurality of contact arms I88 and I81, with the latter arms provided with a bowed rbstion I88. The pairs of contact arms are spaced longitudinally of the rods and extend between shoulders I89, I90; I80, I9I; I8I, I82; I82, I83; and I93, I94 formed on a rockable shaft I85 mounted in the panel I45 and in the plate I85 and extending parallel to the shaft I49. The shoulders I89, I have extending therebetween actuating pins I96 and I91 that are parallel to the shaft I85 but radially spaced therefrom and angularly spaced with respect to each other. These actuating pins I96 and I91 are adapted to engage with the portion I88 of contact arm I81 that is located between said shoulders to close said arm and its cooperating contact arm I 86. The structure just defined constitutes switch 88L A single actuating pin I98 extends between the shoulders I90 and I9I and is adapted in a certain predetermined position to close the contact arms located between said shoulders. This arrangement constitutes switch 882. Between the shoulders I9I and I 92 is an actuating pin I89 which with the contact arms I86 and I81 between said shoulders constitutes switch 883. The shoulders I92 and I921 have extending therebetween an actuating pin 200, which-with the contact arms located between said shoulders constitutes switch 886. The shoulders I93 and I94 carry an actuating pin 20I which with the contact arms between said shoulders constitutes switch 885.

Referring to Figs. 19, 20, 21, 22, and 23 it will be seen that actuating pins I96 and I91 of switch 88I are angularly spaced 30 apart. Also it will be noted that actuating pin I98 of switch 882 is in the same relative position as actuating pin I91 while actuating pin I99 of switch 883 is in the same relative position as actuating pin I96. Likewise it will be observed that actuating pin 20I of switch 885 corresponds in its relative position to actuating pins I99 and I96 already referred to while actuating pin 209 of switch 888- is located in a position displaced 15 from pins I99 and 20I. The shaft I is adapted to be rocked by a knob 202 fixed to the shaft on the front side of the panel I45 and bearing an arrow or other suitable means to cooperate with the indicia "Auto. Safe Stop Set-Up and Hand." When the knob 202 is in the position shown in Fig. 17 with the arrow thereof registered with Safe Stop Set-Up theactuating pin 200 of switch 884 will have contacted the portion I88 of its contract arm I 81 and will have closed the contacts I86 and I81 of said switch while the actuating pins of the remaining switches SSI, 882, 883 and 885 will be out of engagement with the portions I88 of their contact arm I81 and hence the contacts of said switches will be open. When the knob 202 is turned to have the arrow register with the notation Auto. the actuating pins I91 of switch SSI and I 98 of switch 882 will have engaged the portions I88 of their respective contact arms I81 to effect closure of the contact arms I86 and I81 of said switches. At

this time the actuating pins of switches SS3, SS4 and SS5 wil be out of engagement with the portions I88 of their respective contact arms I81 and hence the contact arms of said switches will be open. When the knob 202 is turned to have the arrow registering with the notation Hand" then the actuating pins I96 of switch SSI, I99 of switch SS3 and 20I of switch SS5 will have engaged the portions I88 of their respective contact arms I81 and have effected closure of the contact arms I86 and I8! of said switches. At this time the actuating pins of switches SS2 and SS4 will be outof engagement with the pins I80 of their contact arms I81 and hence the contact arms I88 and I8! of said switches will be open.

The panel I45 is provided with a rockable knob 203 which can be moved to either On position or Off position to actuate a spindle positioning switch SP shown in the diagrams of Figs. 32, 33 and 34. The panel I45 also carries a rockable knob 204 which can be moved to either a low or a high position to actuate two-position switch BG which controls the energization and deenergization of solenoids H4 and 'I I5 to effect engagement of the shiftable clutch element 48 with either the gear 45 or the gear 44. As will later be pointed out the knob 204 is only employed during hand control of the machine since during automatic control of the machine the twoposition switch LSIO controls the 'energization and deenergization of the solenoids H4 and H5.

The panel I45 may also be provided with suitable signal lights 205 and 206 arranged in the control circuit if desired but not shown in thediagrams of Figs. 32, 33 and 34.

The spindle positioning-switch SP controlled by the knob 203 forms a part of a spindle positionin mechanism disclosed in my copending application Serial No. 587,701, filed April 11, 1945, and illustrated herein in Figs. 29 and 30. The

said application issued January 24, 1950, as Pat-' ent No. 2.495.507.

Referring to Figs. 29 and 30 it will be seen that the shaft 42 of the motor 40 is provided with a brake pulley and also is operatively connected with a plugging switch PLS which will be referred to in the description of the diagrams of Figs. 32, 33 and 34. r

The work spindle 39 has mounted thereon a cam ring 208 which is provided on its periphery with a segmental cam portion as clearly shown in my said copending application. This cam ring 208 is adapted to cooperate with a control device forming part of the means for stopping the spindle in predetermined position.- The control device may be a unitary structure which is attached to a support 209 within the headstock. This device comprises a sleeve portion 2I0 which extends through an opening in the support 209 and a bracket portion 2 located on one side of the support 209. The sleeve portion 2 I0 slidably supports a vertically extending rod 2I2 which is held against turning movement in the sleeve portion by suitable means and has its lower end in the form of a fork which mounts a roller 2I3 arranged to contact the periphery of the cam ring 208. The rod 2I2 adjacent its opposite end 18 posed between the collars 2I4 and 2I6. The upper end of the rod 2 I 2 has fixed thereto a laterally projecting switch actuating arm 2I8 which in a certain position of the rod engages and moves the switch button of a normally open micro switch LSO to close said switch.

The bracket portion 2I I has mounted thereon a solenoid PS and the armature 2I9 of said solenoid is pivotally connected to a bent lever arm 220 which is pivoted in turn on the bracket portion 2. The lever arm 220 at its free end is provided with a forked portion which straddles the rod 2I2 just above the movable collar'2IB and is in contact with said collar.. It will be seen that when the solenoid PS is'energized and the armature 2I9 thereof is moved to rock the lever 220' about its pivot in a counterclockwise direction the forked end of the lever will depress the collar 2; and through the spring 2H and fixed collar 2 I4 will act to shift the rod 2 I 2 downwardly against the action of the spring 2I5 and bring the roller 2I3 into contact with the periphery of the cam 208.

This is the relationship of the parts shown in Fig. 29 and it will be noted that at this time the switch actuating arm 2I8 has depressed the switch button of switch LS8 to effect closure of said switch. Each time that the cam portion of the cam ring 208 comes into engagement with the roller 2I3 as the spindle 39 rotates the rod 2I2 will be momentarily raised a sufficient distance to move switch actuating arm 2I8 upwardly and allow switch LS8 to open. During this upward movement of the rod 2I2 the slidable collar 2I6 remains stationary, since it is in contact with the end of the lever arm 220 and hence the spring 2Il is compressed.

In the event that the solenoid PS should be energized at a time when the cam portion of the ring 208 is in position to be engaged by the roller 2 I3 then the rod 2I2 would only move a sufficient distance to engage the roller with said cam portion and the further movement of the lever arm 220 under the action of the solenoid would function to compress the spring 2H and the switch LS8 would remain open. However, as soon as the cam portion of the ring 208 moves out of engagement with the roller then the compressed spring 2|! will move the rod 2I2 downwardly to bring the roller into engagement with the periphery of the cam ring and at such time the switch LSO would be closed as already described.

In Fig. 30 there is disclosed the brake mechanism which cooperates with the drum 201 on the motor shaft 42 to stop said shaft and the work spindle 39 driven thereby in a predetermined position. The brake mechanism comprises a pair of pivoted brake shoes 22I and 222 which are normally moved toward each other and into braking relationship with the pulley 201. The brake shoes 22I and 222 carry at their upper ends remote from their pivots a rod 223 which slides through the upper end of the shoe 22I and is held is provided with a collar 2I4 fixed to the rod and in the upper end of the brake shoe 222 by means of a collar 224 fixed to the rod on one side of said shoe, and a nut 225 screwed onto the rod on the other side of said shoe. The rod 223 carries a coil spring 226 which has one end abutting the outside of the upper end of the brake shoe 22I and its other end abutting an adjustable nut and washer 221 screwed on the rod. The rod 223 intermediate the upper end of the brake shoe 22I and the collar 224 has fixed thereto a second collar 228 with which cooperates the forked end 19 of the arm 229 of a bell crank lever pivoted at 230 to the brake shoe 22l and having its long arm 231 extending beyond the brake shoe 222 and pivotally connected to the armature 232 of the brake soelnoid B.

It will be seen that when the said brake solenoid B is deenergized the armature 232 and the bell crank lever are in the position shown in Fig. 30-and at this time the spring 44 acting on the brake shoe 221 and indirectly on the brake shoe 222 through the rod 223 rocks the said shoes toward each other and into braking engagement with the pulley 281. When the brake solenoid B is energized and the armature 232 is moved inwardly to rock the bell crank lever in a clockwise direction the short arm 228 of said bell crank lever reacts against the collar 228 and since said lever is pivoted to the brake shoe 22l against said shoe, wherefore the brake shoes 22! and 222 will spread apart to non-braking position and this condition holds so long as the solenoid is energized.

The manner in which the solenoids PS and B cooperate and are energized and deenergized to effect the stopping of the work spindle in predetermined position will be pointed out in the description of the wiring diagrams of Figs. 31, 32, 33 and 34 and in the description of the mode of operation of the machine.

All of the switches in the control circuits have been referred to except switch LS9 which is mounted in and carried by the cam disk supporting drum housing 63, see Figs. 7 and 9. The switch LS9 is a two position switch and is normally closed in the low -motor speed position. wherefore when the motor operation is reversed the motor will normally run in reverse at low speed. When the switch 159 is moved to its other operative position, i. e., high motor speed position, then when the motor is reversed the reverse operation will be at high motor speed. This will be more fully explained in connection with the explanation of the diagrams of Figs. 32, 33 and 34. The switch LS9 is operated by a knob 233 which is located exteriorly of the housing portion 63 and carries a pointer 234 which cooperates with the indicia On and Off on a plate 235 secured to the exterior of the housing portion at the front side of the machine. When the switch LS9 is in its normal or low reverse motor speed position the pointer 234 cooperates with the indicia Off and when the switch LS8 is moved to its other operative position, i. e., the high speed reverse motor position, said pointer cooperates with the indicia On.

Referring to the power circuit shown in Figs. 31, 33 and 34, the wires 236, 231 and 238 of a multiphase circuit from a suitable source of electrical energy extend to the main disconnect switch 233 having three contacts DSI, DS2 and DS3. The contacts DSI and DS3 are connected by wires 248' and 2 with the primary of a transformer T, the secondary of which energizes the control circuit disclosed in Figs. 32, 33 and 34.

Referring to Figs. 32, 33 and 34, it will be seen that the wires 248 and 2 are extended from the primary of the transformer T by wires 242 and 243. The 'brake solenoid B is connected to the wire 242 by a wire 244- and to the wire 243 by a wire 245. The switch MS1 is connected by a wire 246 to the wire 242 and by a wire 241 to the wire 3 244. Switch SS4 is in parallel with switch MS1, bein connected to the wire 242 by wire 248 and to the wire 241 by wire 249. Normally open contact FRI of the forward relay is in wire 244, while normally open contact RRI of the reverse relay and normally open contact CR3-4 of relay CR3 are connected to wires 244 and 241 in parallel with normally open contact FR-l Reverting to the power circuit of Figs. 31, 33 and 34 they three contacts of main disconnect switch 238 are connected by wires 250, 251 and 252 with auto transformer ATF. The three contacts of the main disconnect switch 233 are connected by wires 253, 254 and 255 to the contacts F-l, F-2 and F3 of the forward contactor 256, which also includes contact F4 in wire 251 of the reverse portion of the control circuit of Fig. 32, normally closed contact F-5 in wire 258 of the spindle positioning portion of said control circuit and coil F connected to wires 258 and 260 of the forward portion of said control circuit. The contacts Fl F-2 and F-3 of the forward contactor 256 are connected, respectively, by wires 26!, 262 and 263 and wires 264, 265 and 266 to contacts R.l, R2 and R.-3, respectively, of reverse contactor 281, (see Figs. 31, 33 and 34), whereby the polarity of the power circuit can be reversed for reverse operation of the motor 40. The reverse contactor 261 also includes normally closed contact Rr-4 in wire 268 of the forward portion of the control circuit of Figs. 3 33 and 34, normally closed contact R5 in wire 258 of the spindle positioning portion of said control circuit and coil R connected to wire 251 and wire 268 of the reverse portion of said control circuit.

The output sides-of the contacts of the forward contactor 256 and the reverse contactor 261 which are in the power circuit are connected by wires 268, 210 and 2H to the contacts Ll, L2 and L3 of low speed contactor 212 which has four contacts with the fourth contact L4 being located in wire 213 of the high speed portion of the control circuit of Figs. 32. 33 and 34 and with coil L connected to wires 214 and 215 of the low speed portion of said control circuit.

The input sides of the contacts Ll, L2, and L3 are connected by wires 216, 211 and 218 to the contacts Hl, H2 and H3 of the high speed contactor 218, with said three contacts located in the power circuits (see Figs. 31, 33 and 34). At this time it should be noted that high speed contactor 214 also includes contacts H-4 and H5 in the power circuit and contact H6 in wire 215 of the low speed portion of the control circuit of Fig. 32 and coil H connected to wire 213 and wire 280 of the high speed portion of the control circuit.

The input sides of contacts LI, L2 and L-3 of low speed contactor 212 are connected by wires 281, 282 and 283 with contacts CR3-I, CR3-2 and CR3--3 of contactor CR3 (see Figs. 31, 33 and 34) which, as previously mentioned, also has a contact CR34 connected to wires 244 and 241, the brake circuit shown in Figs. 32, 33 and 34 and its coil CR3 connected to wires 258 and 284 of the spindle positioning portion of the control circuit of Figs. 32, 33 and 34'. The contacts CR3-l, CR3-2 and CR.33 of contactor CR3 are connected by wires 285, 286 and 281 to the auto." transformer ATF located in the power circuit.

The output side of contact L-I of low speed contactor 212 is connected by wire 288 to the input side of contact H5 of high speed contactor 219 with said input side of contact H5 being connected by a jumper wire 289 to the input side of contact H--4 of said high speed contactor.

The output sides of contacts L2 and L3 of 

